FEP is similar to Teflon, is highly chemically resistant, sweat and water proof, highly transparent, resistant to sunlight UV and extremely durable. Most IEM cables use a cheap PVC jacket that is softer and not resistant to sweat and oils resulting in greening of the wire. The FEP jacket will keep the conductors safe from oxidation that is commonly found in many earphone cables. While oxidation doesn’t negatively affect the sonic quality of the cable, keeping it out ensures your cable will stay looking great for years. Additionally the dielectric constant of FEP is far better than PVC resulting in a superior sonic improvement.

3.5mm (4-Pole TRRS) is a balanced termination that is compatible with certain high resolution DAPs balanced output such as the Sony ZX2.